New Year resolutions: Why you shouldn’t bother

With the New Year now upon us, many have started to reflect on the past year and what they want to achieve in 2014 – and potentially sinking a lot of money in the process.

Usually coming from the best of intentions, most resolutions taken in early January will focus on health and money. Weight loss, exercise, eating right and quitting smoking, drinking and other unhealthy habits are the most-cited aspirations, according to research company Vitalsmarts.

But Joseph Grenny, co-founder of Vitalsmarts, warns that the failure to stick to New Year's resolutions carries a price tag of more than $1,000 for seven in 10 people.

This price tag, he explained to CNBC, is made up of the "sunk costs spent on quick-fix programs, diet, and other promotions intended to 'guarantee' behavior change" and the costs incurred from the long-term impact on healthcare cost or lost promotions when the resolutions are not achieved.

While January is usually one of the weakest months in terms of retail sales, some products buck the trend. Kitchen equipment (such as smoothie-makers, soup makers and blenders), sportswear and fitness products, smoking cessation products and fresh food are popular in January according to Bryan Roberts, retail analyst at Kantar Retail.

Data compiled by Kantar confirms this. People make an effort to eat fewer sweets and cakes and more fresh fruits and vegetables during the first month of the year, but unfortunately, they quickly reverse the trend again.

In January 2012 and 2013, the U.K. consumed 35.9 and 36.3 tonnes of confectionery products respectively, down from monthly averages of 44.8 and 43.6 tonnes, whereas sales of fresh produce are generally higher in January but quickly decrease again.

(Read more: Retailers to roll out huge after-Christmas deals)

Gym memberships also do very well in January as it fulfills both the "weight loss" and "exercise more" resolutions at the same time.

Fitness First, one of the U.K.'s largest gym chains, told CNBC that compared to the monthly average, January 2012 saw a 76 percent increase in people signing up for new memberships for the year and added that the average London monthly membership costs £30 ($49).

But, as Vitalsmarts highlights, nearly 30 percent of people will give up on their resolutions within the first month and an additional 25.18 percent will give up before the three-month mark. Which could mean that shortly after acquiring the much desired smoothie-maker, it will quickly get shoved at the back of the cupboard, to quietly gather dust.

Or, like one of Vitalsmarts' online survey participant, who enrolled herself in a $150/month gym to deal with her weight issues, you could find yourself spending $3,600 in two years – without actually stepping foot in the facility.